The synthesis of novel heterocycles and their nuclosides will be carried out. The heterocycles will be prepared by the photochemical rearrangement of enaminonitriles. The enaminonitriles will first be condensed with sugars to form nucleosides and the photochemical rearrangment of these to imidazonucleosides will be carried out. The mechanism of this photochemical rearrangement will also be investigated. The chemical synthesis of the nucleoside of 1,6-dihydroimidazo(4,5-d)imidazole will also be carried out.